lei_xsearch: improve curl progress reporting

Instead of having tail(1) follow a file when we're in verbose
mode, unconditionally pipe stderr to a Perl 2-liner which tees
its output to a regular file with line buffering.

POSIX tee(1) isn't suitable for this task since it's required
to be completely unbuffered while we want line-buffering when
running parallel processes.  Fortunately, Perl makes this easy.

This also means we no longer leave curl-err.XXXX files around
on premature shutdown if we're hit by a SIGKILL or similar and
can't exit normally.

We do need to stop and respawn the Perl process if we hit a curl
error, though, since we need to be certain the output is
flushed.

0 files changed, 0 insertions, 0 deletions